I'm providing an answer to your question by quoting from two sources on two architects who were involved in the design of B&O stations and buildings. The first architect was an partnership between John Rudolph Niernsee and James Crawford Neilson. Randolph W. Chalfant & Charles Belfoure's book, Niernsee and Neilson, Architects of Baltimore - Two Careers on the Edge of the Future, provides information and photos of B&O stations, including the Frederick station. The second architect, Ephraim Francis Baldwin, wasn't involved in the original design and construction of the Frederick, MD station, but was involved in a later addition. Carlos P. Avery's book, E. Francis Baldwin, Architect - The B&O, Baltimore, and Beyond provides additional information on the Frederick station, as well as information and photos of other B&O stations and structures.
Here is a quote from Chalfant/Belfoure, p. 69:
"Niernsee & Neilson's 1854 Frederick passenger station at All Saints and Market Streets replaced an 1832 building. This building also had a three-story tower with round arched windows attached to a smaller two-story structure where the passenger waiting area and ticket counter was located. A canopy supported by ornamental iron columns provided cover for arriving and departing passengers. The building still stands in Frederick."
Here is a quote from Avery, p. 40:
"The original B&O station in Frederick, Maryland, was an Italianate building designed by Niernsee in 1854 and built at a cost of about $5,500. It is located on the corner of All Saints and market Streets, in downtown Frederick, at the end of a stub siding. In 1891-92, Baldwin was responsible for an addition to the east end of this station which cost $8,475.50. B&O floor plans for this station are in the Smithsonian collection. Railroad operations to this station ceased in 1948; the building still stands, in restored condition, and is on the National Register of Historic Places."
Wade Rice
Member, B&O RR Historical Society
http://www.borhs.org
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